Harold goofs off too much but is much smarter than people give him credit for, and maybe more so than he realizes. He is a bit hesitant in new situations and will allow kids like Derek to pick on him as opposed to fighting back. Most of all, Harold has a good heart and would do anything for his friends and, for that matter, his family. He loves sports - especially playing on the football team - even though he'll probably never be a star. To Harold the fun is in playing and being part of the team, not just winning. Harold is the strongest kid in school and fortunately uses his strength for good and not evil. In the subatomic world Harold LOVES taking the proton SUV for a spin toward annihilation and, as an up-quark, starts to feel more confident when he discovers how much he really knows and how much he can contribute to his quark "team" of friends.